Marquez was a friend of Mario Vargas Llosa, though their relationship was also fraught with tension. After their early days of friendship, the two did not speak to or see each other for years, until meeting up in Mexico City in 1976. Here, Llosa infamously punched Marquez in the face, and Marquez was shortly afterward photographed sporting a black eye. The photo was published in Times magazine, sparking a public interest in the feud between the two literary giants. However, neither ever commented or shed any light on the incident, or the reason for the fight. In 2007, Llosa agreed to allow part of his book be used as the introduction to the 40th anniversary edition of Marquez's One Hundred Years of Solitude.

In 1958, Marquez participated in the coup d'etat that led to the overthrow and exile of the President of Venezuela, Marcos Perez Jimenez.

Marquez was a close friend of Maria Luisa Elio and her husband Jomi Garcia Ascot. He considered Elio a muse and inspiration. When writing One Hundred Years of Solitude, before he was a famous author, he relied heavily on the couple for writing advice, and would read them different versions of chapters and ask them which they liked best.

Marquez was a close friend of Fidel Castro, who reached out to him because he was a fan of Marquez's writing. Marquez described their relationship as "intellectual," and said that it was based on literature. He praised Castro for being "a very cultured man." Their friendship was the subject of much controversy.

Marquez was strongly against Augusto Pinochet, and even declared in 1976 that he would not publish a novel again until Pinochet was deposed. He called Pinochet's political rule one of "injustice and repression." However, he did end up publishing a novel before Pinochet left office.